Principles of Operation

Parking Aid

Principles of Operation

The parking aid sensors detect objects approximately 152 cm (60 in) from the rear of the vehicle, 50 cm (20 in) from the rear side of the vehicle, and 30 cm (12 in) above the ground. The Parking Aid Module (PAM) calculates the distance to an object within the 170 degree semicircular area around the rear of the vehicle.

A variable-rate warning tone is generated from a speaker attached to the PAM. The speaker increases its warning tone rate as the vehicle gets closer to an obstacle. When an object is detected within 30 cm (12 in) of the sensors, the warning tone becomes continuous. When the PAM sounds the parking aid tone, it sends a volume cutback enabled message to the Body Control Module (BCM) over the High Speed Controller Area Network (HS-CAN). The BCM sends a message to the Audio Control Module (ACM) over the Medium Speed Controller Area Network (MS-CAN). When the ACM receives the message, it reduces the speaker output so the parking aid tone can be heard.

For vehicles that have a base audio system that is not on the Medium Speed Controller Area Network (MS-CAN), the audio speaker output does not reduce when the parking aid tone sounds.

The parking aid system is enabled when the ignition switch is in the RUN position and the transmission in reverse. The parking aid system is disabled if a fault is detected in 1 of the 4 sensors, the parking aid speaker, or the PAM. This is indicated by a parking aid disabled warning message in the message center.

The parking aid system is enabled and disabled through the message center, located in the Instrument Panel Cluster (IPC).

If a MyKey(R) restricted key is in the ignition cylinder, the parking aid menu is not available in the message center and cannot be deactivated.

If the vehicle is equipped with an integrated electronic Trailer Brake Control (TBC) module and a trailer with electric trailer brakes is connected to the vehicle, the parking aid system is disabled.

The PAM communicates on the HS-CAN and can be diagnosed with a scan tool. The PAM communicates with the scan tool, the BCM, the PCM and the IPC.